1. Field of the Invention
The present invention relates to engine intake air filters. More specifically, it relates to a captured tooless fastener for securing the engine intake air filter in the air filter housing and a clamp assembly for closing the air filter housing.
2. Description of Related Art
Many types of vehicles use engine intake air filters. In severe or extreme conditions, it is necessary to routinely replace and/or clean the air filter which is accommodated in an air filter housing.
For example, the United States military M998, 1¼ ton truck, also known as the HMMWV or Hummer, uses an engine intake air filter secured in place by 5/16th inch hex head nut 106. Once, housing cover 112 is removed hex head nut 106 securing the air filter must be removed. To complete the removal and/or installation of air filter 100, a wrench of the correct size must be used to loosen and tighten hex head nut 106. In the field, there is a risk that the wrench will be lost, misplaced, or damaged. If the correct wrench is not available, necessary maintenance cannot be performed and in severe conditions, this can make the vehicle interoperable.
Once removed nut 106 and coordinating sealing washer are removed, they become loose parts. If either part is lost or misplaced air filter 100 cannot be properly reinstalled. If there is no replacement nut 106 and washer, air filter 100 cannot be installed the vehicle is inoperable.
As shown in FIGS. 1 and 3a, once the hex head nut 106 has been removed a ring 102 on the closed end cap 104 of air filter 100 is pulled to remove air filter 100 from housing 110. Ring 102 is a separate piece secured to closed end cap 104. Because ring 102 is a separate piece from closed end cap 104, there is the risk that ring 102 could separate from closed end cap 104 due to careless manufacturing, failed spot welds, excessive force and/or extreme conditions. If ring 102 and closed end cap separate 104, there is no simple way to remove air filter 100.
When an air filter is being installed, there is a risk that the nut will be over torqued using the wrench. This can damage a threaded shaft in the housing that secures the air filter in position. If the threaded shaft is ruined the air filter cannot be replaced and the vehicle is inoperable.
Often people in the field have heavy gloves when replacing the air filter. For example, in some military and industrial situations, the gloves may be hazmat gloves which may not be removed without serious consequences. In other situations, flame retardant or other protective gloves may be needed. The gloves are clumsy and increase the risk that the nut and/or washer will be dropped and lost.
There is a need for an air filter that can be easily installed and removed in the field without tools. There is a need for an air filter than can be replaced without the risk of over torquing the nut. There is a need for an air filter which can be replaced without the risk of losing an essential component. There is also a need for an air filter housing which can be opened and secured without tools and without the risk of losing a component.